The Consumer Rights Act 2015 does cover new and used cars bought from a trader (a franchised dealer or independent garage) but does not cover vehicles bought by private sale, vehicles bought at an auction or vehicles bought for business use. So in this case the car bought must be from a franchised dealer or trader to make the case strong and present it before the court.
Under the Consumer Rights Act, if the vehicle goes wrong within the first 30 days of ownership, the person can simply reject it for a full refund. If a fault develops after those 30 days but within the first six months, the dealer gets one chance to fix it. If they fail to do this, the person is entitled to a full refund, or a partial refund depending on the amount of use the vehicle has had.
If you choose to reject a vehicle, it must be done within the first six months of delivery. All you need is your car, the keys and documentation and take it to your dealer along with a letter outlining the reasons for rejecting the vehicle. So in this case it is quite difficult to reject the car but you can file a case in the consumer court and explain the problem.
Reference: Consumer Rights Act 2015
1.M/S. Honda Siel Cars India Ltd. vs Rohit Jain & Anr. on 31 March, 2016
2.Maruti Udyog Ltd vs Susheel Kumar Gabgotra & Anr on 29 March, 2006
3.Ankur Jain vs Skoda Auto Pvt.Ltd. on 24 May, 2019